<template>
  <li>
    <label for="">
      <input type="checkbox" :checked="todo.done" @change="handleCheck(todo.id)" />
      <!-- 如下代码也能实现功能,但是不推荐,因为有点违反原则,因为修改了props -->
      <!-- <input type="checkbox" v-model="todo.done" /> -->
      <span v-show="!todo.isEdit">{{todo.title}}</span>
      <input ref="inputTitle" v-show="todo.isEdit" type="text" :value="todo.title" @blur="handleBlur(todo,$event)">
    </label>
    <button class="btn btn-danger" @click="handleDelete(todo.id)">删除</button>
    <button v-show="!todo.isEdit" class="btn btn-edit" @click="handleEdit(todo)">编辑</button>
  </li>
</template>
<script>
import pubsub from 'pubsub-js';
export default {
  name: 'MyItem',
  //声明接收todo对象
  props: ['todo'],
  methods: {
    //勾选or取消勾选
    handleCheck(id) {
      //通知App组件将对应的todo的done值取反
      // this.checkTodo(id);
      this.$bus.$emit('checkTodo', id);
    },
    handleDelete(id) {
      if (confirm('确定删除吗')) {
        // this.deleteTodo(id);
        // this.$bus.$emit('deleteTodo', id);
        pubsub.publish('deleteTodo', id);
      }
    },
    //编辑
    handleEdit(todo) {
      if (todo.hasOwnProperty('isEdit')) {
        todo.isEdit = true;
      } else {
        this.$set(todo, 'isEdit', true);
      }
      this.$nextTick(function () {
        this.$refs.inputTitle.focus();
      });
    },
    //失去焦点回调(真正执行修改逻辑)
    handleBlur(todo, e) {
      todo.isEdit = false;
      if (!e.target.value.trim()) {
        return alert('输入不能为空');
      }
      this.$bus.$emit('updateTodo', todo.id, e.target.value);
    }
  }
};
</script>
<style lang="less" rel="stylesheet/less" scoped>
/*item */
li {
  list-style: none;
  height: 36px;
  line-height: 36px;
  padding: 0 5px;
  border-bottom: 1px solid #ddd;
}
li label {
  float: left;
  cursor: pointer;
}
li label li input {
  vertical-align: middle;
  margin-right: 6px;
  position: relative;
  top: -1px;
}
li button {
  float: right;
  display: none;
  margin-top: 3px;
}
li::before {
  content: initial;
}
li:last-child {
  border-bottom: 0;
}
li:hover {
  background-color: #ddd;
}
li:hover button {
  display: block;
}
</style>